Title: When Recording, Sometimes Notes Are Left Sounding
When recording (using the MIDI Player/Recorder), sometimes a note is left sounding long after it was released.
Cause Of Problem:
The Java Sound sequencer does not reliably echo the notes being recorded to the sequencer's output device. Because of this, the KeyMusician Keyboard must continue to send the notes being played to its output device. If the sequencer's output device is the same as the keyboard's output device, this causes 'collisions' where notes get left playing.
Try to ignore it, continuing with the recording. The problem will not appear in the recording itself. It appears to be a problem with the monitoring of the recording. Alternatively, you could stop recording, throw-away what you recorded, and retry the recording again.
If you are recording the entire piece (and don't need to hear other parts, or earlier parts), you could connect the player/recorder to a MIDI interface (or device) that is not connected to anything, or that makes no sound. You can do this because the KeyMusician Keyboard itself, also sends to its own synthesizer, so you will hear what you play anyway.
On Mac OS X (where Java 1.6 must be used), it is bad enough that you're better off using GarageBand for doing your MIDI recording.
Fix Available (in version):
This appears to be much-improved (but not fixed) in versions of Oracle Java 1.7 (as of July 2014), and also in OpenJDK7 (as of April 2014). This remains a bigger problem in Mac OS X, because only Apple Java 1.6 can be used (which does not have the fix).